xref: /freebsd/sbin/ping/ping.c (revision 61afd5bb22d787b0641523e7b9b95c964d669bd5)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Mike Muuss.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 static char copyright[] =
39 "@(#) Copyright (c) 1989, 1993\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif /* not lint */
42 
43 #ifndef lint
44 static char sccsid[] = "@(#)ping.c	8.1 (Berkeley) 6/5/93";
45 #endif /* not lint */
46 
47 /*
48  *			P I N G . C
49  *
50  * Using the InterNet Control Message Protocol (ICMP) "ECHO" facility,
51  * measure round-trip-delays and packet loss across network paths.
52  *
53  * Author -
54  *	Mike Muuss
55  *	U. S. Army Ballistic Research Laboratory
56  *	December, 1983
57  *
58  * Status -
59  *	Public Domain.  Distribution Unlimited.
60  * Bugs -
61  *	More statistics could always be gathered.
62  *	This program has to run SUID to ROOT to access the ICMP socket.
63  */
64 
65 #include <sys/param.h>
66 #include <sys/socket.h>
67 #include <sys/file.h>
68 #include <sys/time.h>
69 #include <signal.h>
70 #include <termios.h>
71 
72 #include <netinet/in_systm.h>
73 #include <netinet/in.h>
74 #include <netinet/ip.h>
75 #include <netinet/ip_icmp.h>
76 #include <netinet/ip_var.h>
77 #include <netdb.h>
78 #include <unistd.h>
79 #include <stdio.h>
80 #include <ctype.h>
81 #include <errno.h>
82 #include <string.h>
83 
84 #define	DEFDATALEN	(64 - 8)	/* default data length */
85 #define	MAXIPLEN	60
86 #define	MAXICMPLEN	76
87 #define	MAXPACKET	(65536 - 60 - 8)/* max packet size */
88 #define	MAXWAIT		10		/* max seconds to wait for response */
89 #define	NROUTES		9		/* number of record route slots */
90 
91 #define	A(bit)		rcvd_tbl[(bit)>>3]	/* identify byte in array */
92 #define	B(bit)		(1 << ((bit) & 0x07))	/* identify bit in byte */
93 #define	SET(bit)	(A(bit) |= B(bit))
94 #define	CLR(bit)	(A(bit) &= (~B(bit)))
95 #define	TST(bit)	(A(bit) & B(bit))
96 
97 /* various options */
98 int options;
99 #define	F_FLOOD		0x0001
100 #define	F_INTERVAL	0x0002
101 #define	F_NUMERIC	0x0004
102 #define	F_PINGFILLED	0x0008
103 #define	F_QUIET		0x0010
104 #define	F_RROUTE	0x0020
105 #define	F_SO_DEBUG	0x0040
106 #define	F_SO_DONTROUTE	0x0080
107 #define	F_VERBOSE	0x0100
108 #define	F_QUIET2	0x0200
109 #define	F_NOLOOP	0x0400
110 #define	F_MTTL		0x0800
111 #define	F_MIF		0x1000
112 
113 /*
114  * MAX_DUP_CHK is the number of bits in received table, i.e. the maximum
115  * number of received sequence numbers we can keep track of.  Change 128
116  * to 8192 for complete accuracy...
117  */
118 #define	MAX_DUP_CHK	(8 * 128)
119 int mx_dup_ck = MAX_DUP_CHK;
120 char rcvd_tbl[MAX_DUP_CHK / 8];
121 
122 struct sockaddr whereto;	/* who to ping */
123 int datalen = DEFDATALEN;
124 int s;				/* socket file descriptor */
125 u_char outpack[MAXPACKET];
126 char BSPACE = '\b';		/* characters written for flood */
127 char DOT = '.';
128 char *hostname;
129 int ident;			/* process id to identify our packets */
130 
131 /* counters */
132 long npackets;			/* max packets to transmit */
133 long nreceived;			/* # of packets we got back */
134 long nrepeats;			/* number of duplicates */
135 long ntransmitted;		/* sequence # for outbound packets = #sent */
136 int interval = 1;		/* interval between packets */
137 
138 /* timing */
139 int timing;			/* flag to do timing */
140 double tmin = 999999999.0;	/* minimum round trip time */
141 double tmax = 0.0;		/* maximum round trip time */
142 double tsum = 0.0;		/* sum of all times, for doing average */
143 
144 int reset_kerninfo;
145 sig_atomic_t siginfo_p;
146 
147 char *pr_addr();
148 void catcher(), finish(), status(), check_status();
149 
150 main(argc, argv)
151 	int argc;
152 	char **argv;
153 {
154 	extern int errno, optind;
155 	extern char *optarg;
156 	struct timeval timeout;
157 	struct hostent *hp;
158 	struct sockaddr_in *to;
159 	struct protoent *proto;
160 	struct termios ts;
161 	register int i;
162 	int ch, fdmask, hold, packlen, preload, sockerrno;
163 	struct in_addr ifaddr;
164 	unsigned char ttl, loop;
165 	u_char *datap, *packet;
166 	char *target, hnamebuf[MAXHOSTNAMELEN], *malloc();
167 #ifdef IP_OPTIONS
168 	char rspace[3 + 4 * NROUTES + 1];	/* record route space */
169 #endif
170 	struct sigaction si_sa;
171 
172 	/*
173 	 * Do the stuff that we need root priv's for *first*, and
174 	 * then drop our setuid bit.  Save error reporting for
175 	 * after arg parsing.
176 	 */
177 	proto = getprotobyname("icmp");
178 	if (proto) {
179 		s = socket(AF_INET, SOCK_RAW, proto->p_proto);
180 		sockerrno = errno;
181 	}
182 
183 	setuid(getuid());
184 
185 	preload = 0;
186 
187 	datap = &outpack[8 + sizeof(struct timeval)];
188 	while ((ch = getopt(argc, argv, "I:LQRT:c:dfh:i:l:np:qrs:v")) != EOF)
189 		switch(ch) {
190 		case 'c':
191 			npackets = atoi(optarg);
192 			if (npackets <= 0) {
193 				(void)fprintf(stderr,
194 				    "ping: bad number of packets to transmit.\n");
195 				exit(1);
196 			}
197 			break;
198 		case 'd':
199 			options |= F_SO_DEBUG;
200 			break;
201 		case 'f':
202 			if (getuid()) {
203 				(void)fprintf(stderr,
204 				    "ping: %s\n", strerror(EPERM));
205 				exit(1);
206 			}
207 			options |= F_FLOOD;
208 			setbuf(stdout, (char *)NULL);
209 			break;
210 		case 'i':		/* wait between sending packets */
211 			interval = atoi(optarg);
212 			if (interval <= 0) {
213 				(void)fprintf(stderr,
214 				    "ping: bad timing interval.\n");
215 				exit(1);
216 			}
217 			options |= F_INTERVAL;
218 			break;
219 		case 'I':		/* multicast interface */
220 			if (inet_aton(optarg, &ifaddr) == 0) {
221 				(void)fprintf(stderr,
222 				    "ping: bad multicast interface.\n");
223 				exit(1);
224 			}
225 			options |= F_MIF;
226 			break;
227 		case 'l':
228 			preload = atoi(optarg);
229 			if (preload < 0) {
230 				(void)fprintf(stderr,
231 				    "ping: bad preload value.\n");
232 				exit(1);
233 			}
234 			break;
235 		case 'L':
236 			options |= F_NOLOOP;
237 			loop = 0;
238 			break;
239 		case 'n':
240 			options |= F_NUMERIC;
241 			break;
242 		case 'p':		/* fill buffer with user pattern */
243 			options |= F_PINGFILLED;
244 			fill((char *)datap, optarg);
245 				break;
246 		case 'Q':
247 			options |= F_QUIET2;
248 			break;
249 		case 'q':
250 			options |= F_QUIET;
251 			break;
252 		case 'R':
253 			options |= F_RROUTE;
254 			break;
255 		case 'r':
256 			options |= F_SO_DONTROUTE;
257 			break;
258 		case 's':		/* size of packet to send */
259 			datalen = atoi(optarg);
260 			if (datalen > MAXPACKET) {
261 				(void)fprintf(stderr,
262 				    "ping: packet size too large.\n");
263 				exit(1);
264 			}
265 			if (datalen <= 0) {
266 				(void)fprintf(stderr,
267 				    "ping: illegal packet size.\n");
268 				exit(1);
269 			}
270 			break;
271 		case 'T':		/* multicast TTL */
272 			i = atoi(optarg);
273 			if (i < 0 || i > 255) {
274 				(void)fprintf(stderr,
275 				    "ping: illegal multicast TTL.\n");
276 				exit(1);
277 			}
278 			ttl = i;
279 			options |= F_MTTL;
280 			break;
281 		case 'v':
282 			options |= F_VERBOSE;
283 			break;
284 		default:
285 			usage();
286 		}
287 	argc -= optind;
288 	argv += optind;
289 
290 	if (argc != 1)
291 		usage();
292 	target = *argv;
293 
294 	bzero((char *)&whereto, sizeof(struct sockaddr));
295 	to = (struct sockaddr_in *)&whereto;
296 	to->sin_family = AF_INET;
297 	to->sin_addr.s_addr = inet_addr(target);
298 	if (to->sin_addr.s_addr != (u_int)-1)
299 		hostname = target;
300 	else {
301 		hp = gethostbyname(target);
302 		if (!hp) {
303 			(void)fprintf(stderr,
304 			    "ping: unknown host %s\n", target);
305 			exit(1);
306 		}
307 		to->sin_family = hp->h_addrtype;
308 		bcopy(hp->h_addr, (caddr_t)&to->sin_addr, hp->h_length);
309 		(void)strncpy(hnamebuf, hp->h_name, sizeof(hnamebuf) - 1);
310 		hostname = hnamebuf;
311 	}
312 
313 	if (options & F_FLOOD && options & F_INTERVAL) {
314 		(void)fprintf(stderr,
315 		    "ping: -f and -i incompatible options.\n");
316 		exit(1);
317 	}
318 
319 	if (datalen >= sizeof(struct timeval))	/* can we time transfer */
320 		timing = 1;
321 	packlen = datalen + MAXIPLEN + MAXICMPLEN;
322 	if (!(packet = (u_char *)malloc((u_int)packlen))) {
323 		(void)fprintf(stderr, "ping: out of memory.\n");
324 		exit(1);
325 	}
326 	if (!(options & F_PINGFILLED))
327 		for (i = 8; i < datalen; ++i)
328 			*datap++ = i;
329 
330 	ident = getpid() & 0xFFFF;
331 
332 	if (!proto) {
333 		(void)fprintf(stderr, "ping: unknown protocol icmp.\n");
334 		exit(1);
335 	}
336 	if (s < 0) {
337 		errno = sockerrno;
338 		perror("ping: socket");
339 		exit(1);
340 	}
341 	hold = 1;
342 	if (options & F_SO_DEBUG)
343 		(void)setsockopt(s, SOL_SOCKET, SO_DEBUG, (char *)&hold,
344 		    sizeof(hold));
345 	if (options & F_SO_DONTROUTE)
346 		(void)setsockopt(s, SOL_SOCKET, SO_DONTROUTE, (char *)&hold,
347 		    sizeof(hold));
348 
349 	/* record route option */
350 	if (options & F_RROUTE) {
351 #ifdef IP_OPTIONS
352 		rspace[IPOPT_OPTVAL] = IPOPT_RR;
353 		rspace[IPOPT_OLEN] = sizeof(rspace)-1;
354 		rspace[IPOPT_OFFSET] = IPOPT_MINOFF;
355 		if (setsockopt(s, IPPROTO_IP, IP_OPTIONS, rspace,
356 		    sizeof(rspace)) < 0) {
357 			perror("ping: record route");
358 			exit(1);
359 		}
360 #else
361 		(void)fprintf(stderr,
362 		  "ping: record route not available in this implementation.\n");
363 		exit(1);
364 #endif /* IP_OPTIONS */
365 	}
366 
367 	if (options & F_NOLOOP) {
368 		if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_LOOP, &loop,
369 		    sizeof(loop)) < 0) {
370 			perror("ping: IP_MULTICAST_LOOP");
371 			exit(1);
372 		}
373 	}
374 	if (options & F_MTTL) {
375 		if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL, &ttl,
376 		    sizeof(ttl)) < 0) {
377 			perror("ping: IP_MULTICAST_TTL");
378 			exit(1);
379 		}
380 	}
381 	if (options & F_MIF) {
382 		if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_IF, &ifaddr,
383 		    sizeof(ifaddr)) < 0) {
384 			perror("ping: IP_MULTICAST_IF");
385 			exit(1);
386 		}
387 	}
388 
389 	/*
390 	 * When pinging the broadcast address, you can get a lot of answers.
391 	 * Doing something so evil is useful if you are trying to stress the
392 	 * ethernet, or just want to fill the arp cache to get some stuff for
393 	 * /etc/ethers.
394 	 */
395 	hold = 48 * 1024;
396 	(void)setsockopt(s, SOL_SOCKET, SO_RCVBUF, (char *)&hold,
397 	    sizeof(hold));
398 
399 	if (to->sin_family == AF_INET)
400 		(void)printf("PING %s (%s): %d data bytes\n", hostname,
401 		    inet_ntoa(*(struct in_addr *)&to->sin_addr.s_addr),
402 		    datalen);
403 	else
404 		(void)printf("PING %s: %d data bytes\n", hostname, datalen);
405 
406 	(void)signal(SIGINT, finish);
407 	(void)signal(SIGALRM, catcher);
408 
409 	/*
410 	 * Use sigaction instead of signal() to get unambiguous semantics
411 	 * for SIGINFO, in particular with SA_RESTART not set.
412 	 */
413 	si_sa.sa_handler = status;
414 	sigemptyset(&si_sa.sa_mask);
415 	si_sa.sa_flags = 0;
416 	if (sigaction(SIGINFO, &si_sa, 0) == -1) {
417 		perror("sigaction");
418 		exit(1);
419 	}
420 
421 	if (tcgetattr(STDOUT_FILENO, &ts) != -1) {
422 		reset_kerninfo = !(ts.c_lflag & NOKERNINFO);
423 		ts.c_lflag |= NOKERNINFO;
424 		tcsetattr(STDOUT_FILENO, TCSANOW, &ts);
425 	}
426 
427 	while (preload--)		/* fire off them quickies */
428 		pinger();
429 
430 	if ((options & F_FLOOD) == 0)
431 		catcher();		/* start things going */
432 
433 	for (;;) {
434 		struct sockaddr_in from;
435 		register int cc;
436 		int fromlen;
437 
438 		check_status();
439 		if (options & F_FLOOD) {
440 			pinger();
441 			timeout.tv_sec = 0;
442 			timeout.tv_usec = 10000;
443 			fdmask = 1 << s;
444 			if (select(s + 1, (fd_set *)&fdmask, (fd_set *)NULL,
445 			    (fd_set *)NULL, &timeout) < 1)
446 				continue;
447 		}
448 		fromlen = sizeof(from);
449 		if ((cc = recvfrom(s, (char *)packet, packlen, 0,
450 		    (struct sockaddr *)&from, &fromlen)) < 0) {
451 			if (errno == EINTR)
452 				continue;
453 			perror("ping: recvfrom");
454 			continue;
455 		}
456 		pr_pack((char *)packet, cc, &from);
457 		if (npackets && nreceived >= npackets)
458 			break;
459 	}
460 	finish();
461 	/* NOTREACHED */
462 }
463 
464 /*
465  * catcher --
466  *	This routine causes another PING to be transmitted, and then
467  * schedules another SIGALRM for 1 second from now.
468  *
469  * bug --
470  *	Our sense of time will slowly skew (i.e., packets will not be
471  * launched exactly at 1-second intervals).  This does not affect the
472  * quality of the delay and loss statistics.
473  */
474 void
475 catcher()
476 {
477 	int waittime;
478 
479 	pinger();
480 	(void)signal(SIGALRM, catcher);
481 	if (!npackets || ntransmitted < npackets)
482 		alarm((u_int)interval);
483 	else {
484 		if (nreceived) {
485 			waittime = 2 * tmax / 1000;
486 			if (!waittime)
487 				waittime = 1;
488 		} else
489 			waittime = MAXWAIT;
490 		(void)signal(SIGALRM, finish);
491 		(void)alarm((u_int)waittime);
492 	}
493 }
494 
495 /*
496  * pinger --
497  *	Compose and transmit an ICMP ECHO REQUEST packet.  The IP packet
498  * will be added on by the kernel.  The ID field is our UNIX process ID,
499  * and the sequence number is an ascending integer.  The first 8 bytes
500  * of the data portion are used to hold a UNIX "timeval" struct in host
501  * byte-order, to compute the round-trip time.
502  */
503 pinger()
504 {
505 	register struct icmp *icp;
506 	register int cc;
507 	int i;
508 
509 	icp = (struct icmp *)outpack;
510 	icp->icmp_type = ICMP_ECHO;
511 	icp->icmp_code = 0;
512 	icp->icmp_cksum = 0;
513 	icp->icmp_seq = ntransmitted++;
514 	icp->icmp_id = ident;			/* ID */
515 
516 	CLR(icp->icmp_seq % mx_dup_ck);
517 
518 	if (timing)
519 		(void)gettimeofday((struct timeval *)&outpack[8],
520 		    (struct timezone *)NULL);
521 
522 	cc = datalen + 8;			/* skips ICMP portion */
523 
524 	/* compute ICMP checksum here */
525 	icp->icmp_cksum = in_cksum((u_short *)icp, cc);
526 
527 	i = sendto(s, (char *)outpack, cc, 0, &whereto,
528 	    sizeof(struct sockaddr));
529 
530 	if (i < 0 || i != cc)  {
531 		if (i < 0)
532 			perror("ping: sendto");
533 		(void)printf("ping: wrote %s %d chars, ret=%d\n",
534 		    hostname, cc, i);
535 	}
536 	if (!(options & F_QUIET) && options & F_FLOOD)
537 		(void)write(STDOUT_FILENO, &DOT, 1);
538 }
539 
540 /*
541  * pr_pack --
542  *	Print out the packet, if it came from us.  This logic is necessary
543  * because ALL readers of the ICMP socket get a copy of ALL ICMP packets
544  * which arrive ('tis only fair).  This permits multiple copies of this
545  * program to be run without having intermingled output (or statistics!).
546  */
547 pr_pack(buf, cc, from)
548 	char *buf;
549 	int cc;
550 	struct sockaddr_in *from;
551 {
552 	register struct icmp *icp;
553 	register u_long l;
554 	register int i, j;
555 	register u_char *cp,*dp;
556 	static int old_rrlen;
557 	static char old_rr[MAX_IPOPTLEN];
558 	struct ip *ip;
559 	struct timeval tv, *tp;
560 	double triptime;
561 	int hlen, dupflag;
562 
563 	(void)gettimeofday(&tv, (struct timezone *)NULL);
564 
565 	/* Check the IP header */
566 	ip = (struct ip *)buf;
567 	hlen = ip->ip_hl << 2;
568 	if (cc < hlen + ICMP_MINLEN) {
569 		if (options & F_VERBOSE)
570 			(void)fprintf(stderr,
571 			  "ping: packet too short (%d bytes) from %s\n", cc,
572 			  inet_ntoa(*(struct in_addr *)&from->sin_addr.s_addr));
573 		return;
574 	}
575 
576 	/* Now the ICMP part */
577 	cc -= hlen;
578 	icp = (struct icmp *)(buf + hlen);
579 	if (icp->icmp_type == ICMP_ECHOREPLY) {
580 		if (icp->icmp_id != ident)
581 			return;			/* 'Twas not our ECHO */
582 		++nreceived;
583 		if (timing) {
584 #ifndef icmp_data
585 			tp = (struct timeval *)&icp->icmp_ip;
586 #else
587 			tp = (struct timeval *)icp->icmp_data;
588 #endif
589 			tvsub(&tv, tp);
590 			triptime = ((double)tv.tv_sec) * 1000.0 +
591 			    ((double)tv.tv_usec) / 1000.0;
592 			tsum += triptime;
593 			if (triptime < tmin)
594 				tmin = triptime;
595 			if (triptime > tmax)
596 				tmax = triptime;
597 		}
598 
599 		if (TST(icp->icmp_seq % mx_dup_ck)) {
600 			++nrepeats;
601 			--nreceived;
602 			dupflag = 1;
603 		} else {
604 			SET(icp->icmp_seq % mx_dup_ck);
605 			dupflag = 0;
606 		}
607 
608 		if (options & F_QUIET)
609 			return;
610 
611 		if (options & F_FLOOD)
612 			(void)write(STDOUT_FILENO, &BSPACE, 1);
613 		else {
614 			(void)printf("%d bytes from %s: icmp_seq=%u", cc,
615 			   inet_ntoa(*(struct in_addr *)&from->sin_addr.s_addr),
616 			   icp->icmp_seq);
617 			(void)printf(" ttl=%d", ip->ip_ttl);
618 			if (timing)
619 				(void)printf(" time=%.3f ms", triptime);
620 			if (dupflag)
621 				(void)printf(" (DUP!)");
622 			/* check the data */
623 			cp = (u_char*)&icp->icmp_data[8];
624 			dp = &outpack[8 + sizeof(struct timeval)];
625 			for (i = 8; i < datalen; ++i, ++cp, ++dp) {
626 				if (*cp != *dp) {
627 	(void)printf("\nwrong data byte #%d should be 0x%x but was 0x%x",
628 	    i, *dp, *cp);
629 					cp = (u_char*)&icp->icmp_data[0];
630 					for (i = 8; i < datalen; ++i, ++cp) {
631 						if ((i % 32) == 8)
632 							(void)printf("\n\t");
633 						(void)printf("%x ", *cp);
634 					}
635 					break;
636 				}
637 			}
638 		}
639 	} else {
640 		/*
641 		 * We've got something other than an ECHOREPLY.
642 		 * See if it's a reply to something that we sent.
643 		 * We can compare IP destination, protocol,
644 		 * and ICMP type and ID.
645 		 */
646 #ifndef icmp_data
647 		struct ip *oip = &icp->icmp_ip;
648 #else
649 		struct ip *oip = (struct ip *)icp->icmp_data;
650 #endif
651 		struct icmp *oicmp = (struct icmp *)(oip + 1);
652 
653 		if ((options & F_VERBOSE) ||
654 		    (!(options & F_QUIET2) &&
655 		     (oip->ip_dst.s_addr ==
656 			 ((struct sockaddr_in *)&whereto)->sin_addr.s_addr) &&
657 		     (oip->ip_p == IPPROTO_ICMP) &&
658 		     (oicmp->icmp_type == ICMP_ECHO) &&
659 		     (oicmp->icmp_id == ident))) {
660 		    (void)printf("%d bytes from %s: ", cc,
661 			pr_addr(from->sin_addr.s_addr));
662 		    pr_icmph(icp);
663 		} else
664 		    return;
665 	}
666 
667 	/* Display any IP options */
668 	cp = (u_char *)buf + sizeof(struct ip);
669 
670 	for (; hlen > (int)sizeof(struct ip); --hlen, ++cp)
671 		switch (*cp) {
672 		case IPOPT_EOL:
673 			hlen = 0;
674 			break;
675 		case IPOPT_LSRR:
676 			(void)printf("\nLSRR: ");
677 			hlen -= 2;
678 			j = *++cp;
679 			++cp;
680 			if (j > IPOPT_MINOFF)
681 				for (;;) {
682 					l = *++cp;
683 					l = (l<<8) + *++cp;
684 					l = (l<<8) + *++cp;
685 					l = (l<<8) + *++cp;
686 					if (l == 0)
687 						(void)printf("\t0.0.0.0");
688 				else
689 					(void)printf("\t%s", pr_addr(ntohl(l)));
690 				hlen -= 4;
691 				j -= 4;
692 				if (j <= IPOPT_MINOFF)
693 					break;
694 				(void)putchar('\n');
695 			}
696 			break;
697 		case IPOPT_RR:
698 			j = *++cp;		/* get length */
699 			i = *++cp;		/* and pointer */
700 			hlen -= 2;
701 			if (i > j)
702 				i = j;
703 			i -= IPOPT_MINOFF;
704 			if (i <= 0)
705 				continue;
706 			if (i == old_rrlen
707 			    && cp == (u_char *)buf + sizeof(struct ip) + 2
708 			    && !bcmp((char *)cp, old_rr, i)
709 			    && !(options & F_FLOOD)) {
710 				(void)printf("\t(same route)");
711 				i = ((i + 3) / 4) * 4;
712 				hlen -= i;
713 				cp += i;
714 				break;
715 			}
716 			old_rrlen = i;
717 			bcopy((char *)cp, old_rr, i);
718 			(void)printf("\nRR: ");
719 			for (;;) {
720 				l = *++cp;
721 				l = (l<<8) + *++cp;
722 				l = (l<<8) + *++cp;
723 				l = (l<<8) + *++cp;
724 				if (l == 0)
725 					(void)printf("\t0.0.0.0");
726 				else
727 					(void)printf("\t%s", pr_addr(ntohl(l)));
728 				hlen -= 4;
729 				i -= 4;
730 				if (i <= 0)
731 					break;
732 				(void)putchar('\n');
733 			}
734 			break;
735 		case IPOPT_NOP:
736 			(void)printf("\nNOP");
737 			break;
738 		default:
739 			(void)printf("\nunknown option %x", *cp);
740 			break;
741 		}
742 	if (!(options & F_FLOOD)) {
743 		(void)putchar('\n');
744 		(void)fflush(stdout);
745 	}
746 }
747 
748 /*
749  * in_cksum --
750  *	Checksum routine for Internet Protocol family headers (C Version)
751  */
752 in_cksum(addr, len)
753 	u_short *addr;
754 	int len;
755 {
756 	register int nleft = len;
757 	register u_short *w = addr;
758 	register int sum = 0;
759 	u_short answer = 0;
760 
761 	/*
762 	 * Our algorithm is simple, using a 32 bit accumulator (sum), we add
763 	 * sequential 16 bit words to it, and at the end, fold back all the
764 	 * carry bits from the top 16 bits into the lower 16 bits.
765 	 */
766 	while (nleft > 1)  {
767 		sum += *w++;
768 		nleft -= 2;
769 	}
770 
771 	/* mop up an odd byte, if necessary */
772 	if (nleft == 1) {
773 		*(u_char *)(&answer) = *(u_char *)w ;
774 		sum += answer;
775 	}
776 
777 	/* add back carry outs from top 16 bits to low 16 bits */
778 	sum = (sum >> 16) + (sum & 0xffff);	/* add hi 16 to low 16 */
779 	sum += (sum >> 16);			/* add carry */
780 	answer = ~sum;				/* truncate to 16 bits */
781 	return(answer);
782 }
783 
784 /*
785  * tvsub --
786  *	Subtract 2 timeval structs:  out = out - in.  Out is assumed to
787  * be >= in.
788  */
789 tvsub(out, in)
790 	register struct timeval *out, *in;
791 {
792 	if ((out->tv_usec -= in->tv_usec) < 0) {
793 		--out->tv_sec;
794 		out->tv_usec += 1000000;
795 	}
796 	out->tv_sec -= in->tv_sec;
797 }
798 
799 /*
800  * status --
801  *	Print out statistics when SIGINFO is received.
802  */
803 
804 void
805 status(sig)
806 	int sig;
807 {
808 	siginfo_p = 1;
809 }
810 
811 void
812 check_status()
813 {
814 	if (siginfo_p) {
815 		siginfo_p = 0;
816 		(void)fprintf(stderr,
817 	"\r%ld/%ld packets received (%.0f%%) %.3f min / %.3f avg / %.3f max\n",
818 		    nreceived, ntransmitted,
819 		    ntransmitted ? nreceived * 100.0 / ntransmitted : 0.0,
820 		    nreceived ? tmin : 0.0,
821 		    nreceived + nrepeats ? tsum / (nreceived + nrepeats) : tsum,
822 		    tmax);
823 	}
824 }
825 
826 /*
827  * finish --
828  *	Print out statistics, and give up.
829  */
830 void
831 finish()
832 {
833 	struct termios ts;
834 
835 	(void)signal(SIGINT, SIG_IGN);
836 	(void)putchar('\n');
837 	(void)fflush(stdout);
838 	(void)printf("--- %s ping statistics ---\n", hostname);
839 	(void)printf("%ld packets transmitted, ", ntransmitted);
840 	(void)printf("%ld packets received, ", nreceived);
841 	if (nrepeats)
842 		(void)printf("+%ld duplicates, ", nrepeats);
843 	if (ntransmitted)
844 		if (nreceived > ntransmitted)
845 			(void)printf("-- somebody's printing up packets!");
846 		else
847 			(void)printf("%d%% packet loss",
848 			    (int) (((ntransmitted - nreceived) * 100) /
849 			    ntransmitted));
850 	(void)putchar('\n');
851 	if (nreceived && timing)
852 		(void)printf("round-trip min/avg/max = %.3f/%.3f/%.3f ms\n",
853 		    tmin, tsum / (nreceived + nrepeats), tmax);
854 	if (reset_kerninfo && tcgetattr(STDOUT_FILENO, &ts) != -1) {
855 		ts.c_lflag &= ~NOKERNINFO;
856 		tcsetattr(STDOUT_FILENO, TCSANOW, &ts);
857 	}
858 
859 	if (nreceived)
860 		exit(0);
861 	else
862 		exit(2);
863 }
864 
865 #ifdef notdef
866 static char *ttab[] = {
867 	"Echo Reply",		/* ip + seq + udata */
868 	"Dest Unreachable",	/* net, host, proto, port, frag, sr + IP */
869 	"Source Quench",	/* IP */
870 	"Redirect",		/* redirect type, gateway, + IP  */
871 	"Echo",
872 	"Time Exceeded",	/* transit, frag reassem + IP */
873 	"Parameter Problem",	/* pointer + IP */
874 	"Timestamp",		/* id + seq + three timestamps */
875 	"Timestamp Reply",	/* " */
876 	"Info Request",		/* id + sq */
877 	"Info Reply"		/* " */
878 };
879 #endif
880 
881 /*
882  * pr_icmph --
883  *	Print a descriptive string about an ICMP header.
884  */
885 pr_icmph(icp)
886 	struct icmp *icp;
887 {
888 	switch(icp->icmp_type) {
889 	case ICMP_ECHOREPLY:
890 		(void)printf("Echo Reply\n");
891 		/* XXX ID + Seq + Data */
892 		break;
893 	case ICMP_UNREACH:
894 		switch(icp->icmp_code) {
895 		case ICMP_UNREACH_NET:
896 			(void)printf("Destination Net Unreachable\n");
897 			break;
898 		case ICMP_UNREACH_HOST:
899 			(void)printf("Destination Host Unreachable\n");
900 			break;
901 		case ICMP_UNREACH_PROTOCOL:
902 			(void)printf("Destination Protocol Unreachable\n");
903 			break;
904 		case ICMP_UNREACH_PORT:
905 			(void)printf("Destination Port Unreachable\n");
906 			break;
907 		case ICMP_UNREACH_NEEDFRAG:
908 			(void)printf("frag needed and DF set (MTU %d)\n",
909 					icp->icmp_nextmtu);
910 			break;
911 		case ICMP_UNREACH_SRCFAIL:
912 			(void)printf("Source Route Failed\n");
913 			break;
914 		case ICMP_UNREACH_FILTER_PROHIB:
915 			(void)printf("Communication prohibited by filter\n");
916 			break;
917 		default:
918 			(void)printf("Dest Unreachable, Bad Code: %d\n",
919 			    icp->icmp_code);
920 			break;
921 		}
922 		/* Print returned IP header information */
923 #ifndef icmp_data
924 		pr_retip(&icp->icmp_ip);
925 #else
926 		pr_retip((struct ip *)icp->icmp_data);
927 #endif
928 		break;
929 	case ICMP_SOURCEQUENCH:
930 		(void)printf("Source Quench\n");
931 #ifndef icmp_data
932 		pr_retip(&icp->icmp_ip);
933 #else
934 		pr_retip((struct ip *)icp->icmp_data);
935 #endif
936 		break;
937 	case ICMP_REDIRECT:
938 		switch(icp->icmp_code) {
939 		case ICMP_REDIRECT_NET:
940 			(void)printf("Redirect Network");
941 			break;
942 		case ICMP_REDIRECT_HOST:
943 			(void)printf("Redirect Host");
944 			break;
945 		case ICMP_REDIRECT_TOSNET:
946 			(void)printf("Redirect Type of Service and Network");
947 			break;
948 		case ICMP_REDIRECT_TOSHOST:
949 			(void)printf("Redirect Type of Service and Host");
950 			break;
951 		default:
952 			(void)printf("Redirect, Bad Code: %d", icp->icmp_code);
953 			break;
954 		}
955 		(void)printf("(New addr: 0x%08lx)\n", icp->icmp_gwaddr.s_addr);
956 #ifndef icmp_data
957 		pr_retip(&icp->icmp_ip);
958 #else
959 		pr_retip((struct ip *)icp->icmp_data);
960 #endif
961 		break;
962 	case ICMP_ECHO:
963 		(void)printf("Echo Request\n");
964 		/* XXX ID + Seq + Data */
965 		break;
966 	case ICMP_TIMXCEED:
967 		switch(icp->icmp_code) {
968 		case ICMP_TIMXCEED_INTRANS:
969 			(void)printf("Time to live exceeded\n");
970 			break;
971 		case ICMP_TIMXCEED_REASS:
972 			(void)printf("Frag reassembly time exceeded\n");
973 			break;
974 		default:
975 			(void)printf("Time exceeded, Bad Code: %d\n",
976 			    icp->icmp_code);
977 			break;
978 		}
979 #ifndef icmp_data
980 		pr_retip(&icp->icmp_ip);
981 #else
982 		pr_retip((struct ip *)icp->icmp_data);
983 #endif
984 		break;
985 	case ICMP_PARAMPROB:
986 		(void)printf("Parameter problem: pointer = 0x%02x\n",
987 		    icp->icmp_hun.ih_pptr);
988 #ifndef icmp_data
989 		pr_retip(&icp->icmp_ip);
990 #else
991 		pr_retip((struct ip *)icp->icmp_data);
992 #endif
993 		break;
994 	case ICMP_TSTAMP:
995 		(void)printf("Timestamp\n");
996 		/* XXX ID + Seq + 3 timestamps */
997 		break;
998 	case ICMP_TSTAMPREPLY:
999 		(void)printf("Timestamp Reply\n");
1000 		/* XXX ID + Seq + 3 timestamps */
1001 		break;
1002 	case ICMP_IREQ:
1003 		(void)printf("Information Request\n");
1004 		/* XXX ID + Seq */
1005 		break;
1006 	case ICMP_IREQREPLY:
1007 		(void)printf("Information Reply\n");
1008 		/* XXX ID + Seq */
1009 		break;
1010 	case ICMP_MASKREQ:
1011 		(void)printf("Address Mask Request\n");
1012 		break;
1013 	case ICMP_MASKREPLY:
1014 		(void)printf("Address Mask Reply\n");
1015 		break;
1016 	case ICMP_ROUTERADVERT:
1017 		(void)printf("Router Advertisement\n");
1018 		break;
1019 	case ICMP_ROUTERSOLICIT:
1020 		(void)printf("Router Solicitation\n");
1021 		break;
1022 	default:
1023 		(void)printf("Bad ICMP type: %d\n", icp->icmp_type);
1024 	}
1025 }
1026 
1027 /*
1028  * pr_iph --
1029  *	Print an IP header with options.
1030  */
1031 pr_iph(ip)
1032 	struct ip *ip;
1033 {
1034 	int hlen;
1035 	u_char *cp;
1036 
1037 	hlen = ip->ip_hl << 2;
1038 	cp = (u_char *)ip + 20;		/* point to options */
1039 
1040 	(void)printf("Vr HL TOS  Len   ID Flg  off TTL Pro  cks      Src      Dst\n");
1041 	(void)printf(" %1x  %1x  %02x %04x %04x",
1042 	    ip->ip_v, ip->ip_hl, ip->ip_tos, ntohs(ip->ip_len),
1043 	    ntohs(ip->ip_id));
1044 	(void)printf("   %1x %04x", (ntohl(ip->ip_off) & 0xe000) >> 13,
1045 	    ntohl(ip->ip_off) & 0x1fff);
1046 	(void)printf("  %02x  %02x %04x", ip->ip_ttl, ip->ip_p,
1047 							    ntohs(ip->ip_sum));
1048 	(void)printf(" %s ", inet_ntoa(*(struct in_addr *)&ip->ip_src.s_addr));
1049 	(void)printf(" %s ", inet_ntoa(*(struct in_addr *)&ip->ip_dst.s_addr));
1050 	/* dump any option bytes */
1051 	while (hlen-- > 20) {
1052 		(void)printf("%02x", *cp++);
1053 	}
1054 	(void)putchar('\n');
1055 }
1056 
1057 /*
1058  * pr_addr --
1059  *	Return an ascii host address as a dotted quad and optionally with
1060  * a hostname.
1061  */
1062 char *
1063 pr_addr(l)
1064 	u_long l;
1065 {
1066 	struct hostent *hp;
1067 	static char buf[80];
1068 
1069 	if ((options & F_NUMERIC) ||
1070 	    !(hp = gethostbyaddr((char *)&l, 4, AF_INET)))
1071 		(void)snprintf(buf, sizeof(buf), "%s",
1072 		    inet_ntoa(*(struct in_addr *)&l));
1073 	else
1074 		(void)snprintf(buf, sizeof(buf), "%s (%s)", hp->h_name,
1075 		    inet_ntoa(*(struct in_addr *)&l));
1076 	return(buf);
1077 }
1078 
1079 /*
1080  * pr_retip --
1081  *	Dump some info on a returned (via ICMP) IP packet.
1082  */
1083 pr_retip(ip)
1084 	struct ip *ip;
1085 {
1086 	int hlen;
1087 	u_char *cp;
1088 
1089 	pr_iph(ip);
1090 	hlen = ip->ip_hl << 2;
1091 	cp = (u_char *)ip + hlen;
1092 
1093 	if (ip->ip_p == 6)
1094 		(void)printf("TCP: from port %u, to port %u (decimal)\n",
1095 		    (*cp * 256 + *(cp + 1)), (*(cp + 2) * 256 + *(cp + 3)));
1096 	else if (ip->ip_p == 17)
1097 		(void)printf("UDP: from port %u, to port %u (decimal)\n",
1098 			(*cp * 256 + *(cp + 1)), (*(cp + 2) * 256 + *(cp + 3)));
1099 }
1100 
1101 fill(bp, patp)
1102 	char *bp, *patp;
1103 {
1104 	register int ii, jj, kk;
1105 	int pat[16];
1106 	char *cp;
1107 
1108 	for (cp = patp; *cp; cp++)
1109 		if (!isxdigit(*cp)) {
1110 			(void)fprintf(stderr,
1111 			    "ping: patterns must be specified as hex digits.\n");
1112 			exit(1);
1113 		}
1114 	ii = sscanf(patp,
1115 	    "%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x%2x",
1116 	    &pat[0], &pat[1], &pat[2], &pat[3], &pat[4], &pat[5], &pat[6],
1117 	    &pat[7], &pat[8], &pat[9], &pat[10], &pat[11], &pat[12],
1118 	    &pat[13], &pat[14], &pat[15]);
1119 
1120 	if (ii > 0)
1121 		for (kk = 0;
1122 		    kk <= MAXPACKET - (8 + sizeof(struct timeval) + ii);
1123 		    kk += ii)
1124 			for (jj = 0; jj < ii; ++jj)
1125 				bp[jj + kk] = pat[jj];
1126 	if (!(options & F_QUIET)) {
1127 		(void)printf("PATTERN: 0x");
1128 		for (jj = 0; jj < ii; ++jj)
1129 			(void)printf("%02x", bp[jj] & 0xFF);
1130 		(void)printf("\n");
1131 	}
1132 }
1133 
1134 usage()
1135 {
1136 	(void)fprintf(stderr,
1137 	    "usage: ping [-LQRdfnqrv] [-c count] [-i wait] [-I interface]\n\t[-l preload] [-p pattern] [-s packetsize] [-T ttl] host\n");
1138 	exit(1);
1139 }
1140